IN THIS ISSUE. Industry News and Developments INDUSTRY NEWS AND DEVELOPMENTS. SPOTLIGHT Headphone Testing (Part 1) The Basics

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1 V O L U M E 2 5, I S S U E 2 D E C E M B E R INDUSTRY NEWS AND DEVELOPMENTS By Vance Dickason Industry News and Developments By Vance Dickason IN THIS ISSUE SPOTLIGHT Headphone Testing (Part 1) The Basics By Steve Temme TEST BENCH New Ribbon from FPS and Two 4" Drivers from SB Acoustics By Vance Dickason SPOTLIGHT MoTIV Loudspeaker Magnetics Modeler By Rob Baum INDUSTRY WATCH By Vance Dickason Products & Services Index CES 2012 The 2012 International Consumer Electronics Show (Number 44 the first one launched in June 1967 in New York City with 200 exhibitors and 17,500 attendees) will be held this year from January 10 13, 2012 in Las Vegas, Nevada. This year s International CES will feature product debuts from more than 2,700 exhibitors, covering more than 30 product areas, including the latest in content, wireless, digital imaging, mobile electronics, home theater, and audio, including a focus on electric vehicles and in-vehicle technology (see Photo 1). With a focus on green technology, it s interesting to note that the Consumer Electronics Association (CEA) announced that the 2009 International CES was named North America s Greenest Show by Trade Show Executive (TSE) magazine. CEA was awarded the highly coveted Leader in Green Initiatives Gold Grand Award for outstanding green presence in producing the world s largest consumer technology tradeshow, the International CES. Topping that off, CEA recently Testing a 4" woofer, p. 23 A head-and-torso simulator, p. 15 announced that the 2010 International CES was named both the largest tradeshow and the tradeshow with the highest economic impact by TSE magazine. CEA was awarded the highly coveted number one spot in TSE s Gold 100 Rankings of CES has earned top honors as the largest annual tradeshow in each of the four years of the Gold 100 Photo 1: A view of last year's International CES

2 NEW + = SoundCheck s CLEAR TM Listen Inc. TM Full Page Perceptual Rub & Buzz When it comes to increasing yield, you only want to reject speakers that sound bad. Listen s new CLEAR Perceptual Rub & Buzz algorithm is your fully automated, 100% reliable golden ear. Used on the production line, it accurately replicates the response of a human listener to give you fully automated pass/fail measurements with intelligence. Low cost True Perceptual Rub & Buzz detection Insensitive to background noise Excellent correlation to the human ear Scan for more info Visit for a FREE demo and 20% discount* * Discount applies to CLEAR module (part number 2030) only. See web site for full terms and conditions. Tel: sales@listeninc.com Web:

3 TRUEXTENT TECH BRIEF Tuning Forks: Let Your Ears Do The Math! Peter J. Andrews, Sr. Electro-Acoustics Engineer While many audiophiles and engineers are aware that beryllium is the lightest and stiffest metal for electro-acoustic transducers, it is perhaps not easy to grasp the vast performance advantages it has over other common lightweight metals from a theoretical discussion like our white paper 1. For an easily audible demonstration, we machined three tuning forks to the exact same dimensions; one made of aluminum, one of titanium, and one of beryllium. We hope you had a chance to ping these at a recent trade show demonstration. The first thing you might notice when picking up the three forks is the difference in weight, with the titanium feeling much heavier in your hands compared to the other two. Titanium, of course, has a relatively high density, at 4.50g/cm 3. The aluminum fork is definitely lighter, at 2.70g/cm 3, and the beryllium fork even lighter than that, only 1.85g/cm 3. The actual masses of our example tuning forks are: Aluminum Fork = 55.7 g (2.0 oz.) Titanium Fork = 93.7 g (3.3 oz.) Beryllium Fork = 38.5 g (1.4 oz.) The next thing you might notice is that the aluminum and titanium forks ring at nearly the same pitch (roughly C5) when struck on a hard surface, but the beryllium rings at a much higher pitch (roughly E6). Even though titanium is ~1.6x stiffer than aluminum, it is also ~1.7x heavier, giving essentially the same resonant frequency in both materials. ELECTROFUSION South Grimmer Boulevard Fremont, CA truextent@materion.com MATERION CORPORATION

4 Award s existence. Building upon its green initiatives, the 2012 CES will again feature the Sustainable Planet TechZone, sponsored by Earth 911, which will showcase world-changing technologies that benefit the environment, utilize new forms of sustainable energy, renew resources and contribute to the global development. This exhibit area will feature products and services that make it possible for everyone to stay connected, informed, and live sustainable lifestyles. The GoElectricDrive TechZone will also highlight the latest technology behind electric vehicles for consumers seeking to live more sustainably through alternative transportation. Also featured will be more than 200 conference sessions and over 500 speakers designed to help educate attendees on the latest consumer electronic trends. This year s show is expected to be about the same size as last year s (2,700 exhibitors in 2009, 2,500 for 2010, and 2,700 in 2011), with about 140,000 persons expected to attend (2011 was 141,000, 2010 was 120,000, 2009 s about 110,000, and 141,150 in 2008). The 2012 CES will, like the 2011 Show (see Photo 2), be centralized at the Las Vegas Convention Center (LVCC) and the Las Vegas Hilton, with the Sands Convention Center no longer being part of the 2012 show. The Venetian will still provide display space for high-performance audio. Keynote speakers at this year s show will include: Steve Ballmer, CEO of Microsoft; Dr. Paul E. Jacobs, chairman and CEO of Qualcomm; Dieter Zetsche, chairman of the Board of Management of Daimler AG and head of Mercedes-Benz Cars; and Hans Vestberg, president and CEO of Ericsson Group. A partial list of loudspeaker manufacturers and other relevant exhibitors includes Aamp of America, Acousticom, Acoustic Innovation Limited, Acoustic Technologies, Adam Audio USA, Alpine Electronics, Altec Lansing, Amphion Loudspeakers Ltd., Anthony Gallo Acoustics, Aperion Inc., Arcam, Audioengine, Audiovox, Avantgarde Acoustic GmbH, Bang & Olufsen America Inc., Blumenhofer Acoustics, Cadence Acoustics Ltd., Cambridge Audio, CDT Audio, Cerwin Vega mobile, Clarion, db Drag Racing Association, DEQX Pty Ltd., DeVore Fidelity Ltd., Dynaudio, Earthquake Sound, Eggleston Works, Focal- JM Labs, Focus Audio, Genesis Advanced Technologies, Gibson Guitar Corp., GoldenEar Technology, Hansen Audio, Harman Lifestyle, Photo 2: A view of the 2011 CES show IASCA, IEEE - Institute of Electrical and Electronic Eng, JL Audio, Joseph Audio, KEF America, Kenwood USA, Kicker, Klipsch Group, Lawrence Audio, Legacy Audio, Line 6, Inc., Logitech, LOUDsoft, Magico LLC, Marten, MartinLogan, McIntosh, Meiloon Industrial, Meridian American, MBL America, Memphis Car Audio, Meridian America, Mitek, Monster, Mordaunt-Short, Monitor Audio, Morel, Motus Audio, Neat Acoustics, Nola Speakers, NTTAudiolab, Onkyo USA, Opera Loudspeakers, Orca Electronics/Focal America, Paradigm Electronics, Parasound, Peerless Fabrikkerne (India) Ltd., Pioneer Electronics/TAD, Polk Audio, PowerBass USA, Prism Technology, Proac USA, PSB Speakers, Pure Acoustics, Pyle Audio, Raidho Acoustics, RBH Sound, Rel Acoustics, Russound, Samson Technologies, SB Acoustics, Shanghai Silver Flute, Sonavox, Sony, Swans Speaker System, Thiel Audio, THX Ltd., Tivoli Audio, Totem Acoustics, Usher Audio, Vandersteen Audio, Velodyne Acoustics, Vienna Acoustics, Waterfall Audio, WBT USA, Westlake Audio, Wharfedale, Wilson Audio, Wisdom Audio, and YG Acoustics. Going through this list, it is readily apparent that a lot of the usual suspects will be again absent this year. For more on this year s CES, visit the CES website at com. ALMA Winter Symposium The Future of Loudspeakers ALMA, the International Loudspeaker Association, Winter Voice Coil, (ISSN X), the Periodical of the Loudspeaker Industry, is published monthly by Segment, LLC, 4 Park St., Vernon, CT USA, (860) , FAX (860) Periodical rates paid at Vernon, CT and additional offices. Copyright 2011 by Segment, LLC. All rights reserved. Quotation from Voice Coil is forbidden without written permission of the publisher. Publisher - Hugo Van haecke Editor - Vance Dickason ( vdc@northwest.com) C. J. Abate...Editorial Coordinator Shannon Becker...Editorial Assistant Shannon Barraclough...Marketing Director KC Prescott...Graphics Jeff Yanco...Controller Debbie Lavoie...Customer Service Valerie Luster...Administrative Coordinator Submissions Send all press releases and information to Voice Coil, Segment, LLC Editorial Dept., 4 Park St., Vernon, CT 06066, or FAX us material at (860) , or editorial@audioxpress.com. ADVERTISING For advertising reservations contact: Strategic Media Marketing, Inc., 2 Main St., Gloucester, MA USA, Phone: (978) , or Fax: , Toll-free (800) , peter@smmarketing.us. Erica Fienman with artwork inquiries at: advertising@audioxpress.com. Qualified subscriptions to Voice Coil run for one year. Renew annually on-line at voicecoilmagazine.com/vcqual.html Subscriptions to Voice Coil are available in printed and digital versions. To subscribe to the digital version, please visit our website at and complete a qualification form. When you qualify, you will receive an confirming your subscription. The current issue of each digital Voice Coil will be posted to at the end of the month. To access, use the link in the notification, or you can simply log in to the website to view your issue along with the archived issues. For those overseas, the cost of a printed subscription is $ per year. Please contact customer service or order your subscription online at 4 VOICE COIL

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6 Symposium program, The Future of Loudspeakers, starts the last day of CES, Friday, January 13, and Saturday, January 14, at The Riviera Hotel in Las Vegas. It will feature some popular training sessions by noted loudspeaker industry experts. Dr. Floyd Toole will present his popular full-day training session Loudspeakers and Rooms: Designing Listening Experiences, based on his recently published book, Sound Reproduction. This session explores loudspeaker and in-room measurements and their interpretation in terms of listener perception. Half-day trainings will feature Active Noise Cancellation Special Considerations for Loudspeakers and Microphones, by Mike Klasco of Menlo Scientific, and Cone Vibration and Sound Radiation, by Dr. Wolfgang Klippel. There will be a panel of world-class experts discussing the topic of Neodymium: Coping with the Consequences of Supply and Demand Elasticity. Panel Chairman Spiro Iraclianos of Harman International will continue this discussion begun at the International AES. The use of neodymium iron boron magnets has been increasing over the last few decades to address the demands of compact, high-energy motor applications. Loudspeakers have been adapting the super magnets to delicately balance the size/performance ratio demands in today s marketplace. In recent months, the availability of neodymium has been shrinking while the cost of the magnets, which use the rare earth element, has skyrocketed. The workshop will serve as a forum for industry professionals, from all aspects of the value chain, to gather and collectively discuss, and begin to address the facts and myths surrounding the global issue, which has caused significant paradigm shifts in the way we think about the future of the industry. The Symposium, the largest event in the world entirely dedicated to the loudspeaker industry, will feature training courses on various aspects of loudspeaker modeling, test and measurement and manufacturing. In addition, there will be technical paper presentations, tutorial sessions, round table and panel discussions, an exhibit hall, showcasing suppliers to the industry and plentiful networking opportunities. The ALMA Winter Symposium will overlap and parallel The International Conference on Consumer Electronics (ICCE), presented by the IEEE Consumer Electronics Society, which will take place January 13 16, within the North Hall of the Las Vegas Convention Center, an easy commute to The Riviera. The ALMA Board of Directors, in consideration of the program theme relating to the future of loudspeakers, have committed to facilitating opportunities for knowledge-sharing by paralleling the two programs and moving to this new location. The ICCE is where key technologies, products, services, and architectures for consumer entertainment and information delivery are first presented (see for more information). Please note, the Winter Symposium program will convene on different dates in It begins on the last day of the CES in Las Vegas. The symposium lasts two days, Friday, January 13, and Saturday, January 14. It will be VOICE COIL

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8 held in a new location, The Riviera Hotel. Hotel rooms are blocked at The Riviera under the CES from January 6 15 and under ALMA International, from January Visit the ALMA website at to register to attend or exhibit, and for more information. Call for Papers: AES Conference on Music- Induced Hearing Disorders The Audio Engineering Society (AES) has issued a call for papers to be presented at its 47 th conference event. The conference is titled Music-Induced Hearing Disorders: New Technologies for Measurement and Protection, and will highlight the state of the art in hearing loss prevention strategies and devices related to music production and reproduction. The event (see Photo 3) will take place at Columbia College in Chicago, June 20 22, Researchers, including those from both the audiology and pro audio fields, are invited to submit papers for presentation at the conference. Proposed topics for presentation include: Standards and Guidelines for Hearing Exposure and Protection; Active and Passive Hearing Protection Devices; Hearing Exposure Measurement and Control Devices; Technologies for Monitoring and Controlling Consumer Audio Devices; Sound Level Management for Live Sound Events; Electronic Devices for Hearing Impaired Musicians and Sound Engineers; and other related topics. The conference committee invites the submission of manuscripts (4 to 10 pages, maximum 3,000 words) for SPECIALIZING IN high-temperature edge-wound and multiple layer flat-wound coils for the pro audio, home theater, and automotive aftermarket Photo 3: The conference will highlight the state of the art in hearing loss prevention strategies and devices consideration. Papers should be submitted by January 15, 2012, and may address the above topic list, or other areas relevant to the conference. Papers should include a problem statement, work performed, methods employed, conclusions and significance of the work. Each submission will be reviewed by the conference committee, and authors notified of acceptance for inclusion well in advance of the conference. The conference also invites proposals for workshops and tutorials. Interested parties should submit a 125-word abstract, with possible participants, duration, and facility needs to the conference committee before January 15, The AES 47 th International Conference is being chaired by Dr. Michael Santucci, Au.D., a practicing audiologist, AES member, and president of Sensaphonics. Co-chairs for papers are Joerg Bitzer and Robert Schulein. The Call for Papers for the Conference on Music-Induced Hearing Disorders can be downloaded (PDF) at: org/conferences/47/downloads/47thcallforpapers.pdf. The document includes addresses for further inquires. PMI Information Library The Performance Media Industries website, blog, and - Highest quality domestic or imported coils. - Custom coils available in: Multi-layer wire configurations Multiple lead configurations Round and Flat Wire Custom lead-out attachments Free standing coils Multiple wire types Bifilar or Edgewound Custom bobbin wound coils - High temperature adhesive coated Copper and Aluminum wire in round and flat sizes. CCAW wire available in round sizes. - Adhesive coated custom cut forms and Collars. - Custom slit rolls of Form and Collar material available coated or uncoated North Fork Drive, North Fort Myers, Florida Phone (239) Fax (239) For samples, information, or a quotation, please contact Jon Van Rhee at jon@precisioneconowind.com Visit us on the web at Photo 4: The Performance Media Industries website, blog, and Facebook pages offer information on audio topics 8 VOICE COIL

9 Facebook pages offer a wide range of white papers, articles, and how-to guides by Anthony Grimani on the topics of audio, acoustics, calibration, and much more (see Photo 4). Here are links to some of these guides which you can easily downloadable PDF s for reading and reference: 1. Can You Tune a Theater? Most people think that calibration consists of setting the levels of the A/V controller and maybe also the delay times and speaker configuration selections. In fact, there are many, many other steps involved in the full-on tuning of a system. Skip any one of them, and you may be sacrificing performance. 2. The Foundation of Acoustics Acoustics play a vital role in the sound of a home theater. Consider this: In a typical listening room, when you sit 12' from the front speakers you are actually listening to more reflected sound energy from the room than direct sound energy from the speakers. Thus, the room s acoustic thumbprint affects more than 50% of the sound you hear. Isn t that reason enough to carefully design the character of that thumbprint? 3. Bass-ics Other than sticking it in your ear, what can you do with a sound level meter?! You can use it to tune the level of a subwoofer, but proceed carefully! Go to the PMI website, to download these informative white papers. REFINE YOUR DESIGNS AND CONTROL OVERLOOKED VARIABLES WITH SAATI ACOUSTEX MESH Saati has woven the Acoustex line to ensure predictable sound transparency, consistent acoustical damping for tweeters, planar speakers, headphones, mic wind screens, mobile devices & other transducers ACOUSTEX LINE Transparency Damping Acoustically transparent mesh Acoustical damping barriers Moisture and dust protection Conductive screens -EMI/RFI shielding Regulates and controls airflow Fabric dyed to any color Hyphobe water-repellent treatment Special MET metallized finishes ITALY Paolo Debandi PDebandi@saati.com USA Paul Cylenica PCylenica@saati.com CONTACT CHINA Fabrizio Legrenzi FLegrenzi@saati.com ALMA 2012WINTER SYMPOSIUM January 13-14, 2012 The Riviera Hotel,Las Vegas THE FUTURE OF LOUDSPEAKERS The largest event held in the world entirely dedicated to the loudspeaker industry! Register today for focused learning sessions, thought-provoking speakers, a solution-filled exhibit hall and plenty of networking opportunities. FEATURED TRAININGS: Active Noise Cancellation Special Considerations for Loudspeakers and Microphones" by Mike Klasco, Menlo Scientific Cone Vibration and Sound Radiation by Dr. Wolfgang Klippel Loudspeakers and Rooms: Designing Listening Experiences by Dr. Floyd Toole Panel: Neodymium: Coping with the Consequences of Supply and Demand Elasticity The International Loudspeaker AssociationALMA REGISTER ONLINE AT NEW DATES! NEW VENUE! PLUS Papers Tutorials Exhibits Business Solutions Networking Career Center Member Dinner Driver Awards and MORE! Find us at Booth # 5208, in the North Hall at CES INTERNATIONAL DECEMBER

10 Adhesive Materials Group Launches New Site Houston-based Adhesive Materials Group (AMG) is pleased to announce their new site dedicated to providing customers ready access to adhesive repackaging solutions. The company felt it needed a better way to deliver higher value to new and existing customers. Its website, www. adhesivematerialsgroup.com, can now boast one of the largest adhesive portfolios on the Internet, offering customers access to an unlimited number of configurations from well-known manufacturers such as 3M, Henkel, Loctite and others. Adhesive Materials Group was founded in 1980 and is a division of Hisco, Inc., a provider of electronic and industrial materials. New Pro Sound Transducers from BMS BMS has recently released the following new pro sound drivers: BMS 4528: The 4528 is a 1" neodymium high-frequency compression driver and waveguide. Features include 200-W peak power handling, 113-dB sensitivity, a frequency range of 1.2 to 30 khz with a recommended crossover of 1800 Hz, and a 1" voice coil wound with copper-clad aluminum wire on a Kapton former with a polyester diaphragm. BMS Low-Midrange Cone Drivers: BMS has released two new low-midrange drivers, the 5" 5S117 and the 6.5" 6S117. Both midranges feature 130-W power handling, 1.5"-diameter copper sandwich voice coils, triple 5S117 6S117 Fs 95 Hz 80 Hz Revc 11.4 Ω 11.4 Ω Qms Qes Qts Vas 3.25 ltr 10.4 ltr Sd m m 2 Xmax 5 mm 5 mm Sens. 91. db (1 W/1 m) 93 db 9 (1 W/1 m) Table 1: Parameters for the 5S117 smf 6S117 drivers aluminum shorting rings, cast aluminum frames, doubletreated waterproof paper cones, and a nominal 16-Ω impedance. Parameters are as noted in Table 1. For more information, visit the BMS website at www. bmsspeakers.com. VC 10 VOICE COIL

11 Spotlight Headphone Testing (Part 1) The Basics By Steve Temme, Listen, Inc. Introduction As more and more loudspeaker engineers find themselves employed in the fast-growing headphone market, either through company diversification or changing jobs, it is important that the unique challenges of testing headphone packages are fully understood. Many of the characteristics that make for a good inroom listening experience with a loudspeaker good frequency response, low distortion, no Rub & Buzz or loose particles, etc. also apply to headphones, and many of the principles of loudspeaker test apply. However, there are some major differences and additional issues that need to be taken into account. These include couplers and associated correction curves, acoustic seal, fixturing, and additional tests such as L/R tracking. In this article, we discuss the issues that are common to testing all types of headphones. In Part 2 (a future article) we will address the specific needs of special cases of headphones such as Bluetooth and USB headphone testing, noise-cancelling headphones, and Max SPL measurements to prevent hearing loss. Similarities and Differences First, let us look at the similarities in testing loudspeakers and headphones. The set-up essentially consists of an electroacoustic measurement system, some kind of ear simulator containing a reference microphone, and the device under test. A test signal is sent to the transducer (headphone), which in turn is measured by a reference microphone in a coupler. The basic measurements made on headphones are very similar to those made on loudspeakers. These include frequency response, phase (polarity), distortion (THD and Rub & Buzz), and impedance. In both cases, the test signal is usually a swept sine wave, and the level can vary. Some set the drive level to achieve a certain sound pressure level at a given frequency; others choose the level that equates to 1 mw of power. Certain products may necessitate testing the frequency response at one level and performing a second, higher level test for distortion. Now, let us look at the differences. The primary difference in the test set up between a loudspeaker and a headphone measurement is in the way in which the transducer interacts with the microphone. Whereas loudspeakers are tested in open air, a headphone or earphone must be presented with an acoustic load that simulates the human ear. It is common to compare the left and right-channel frequency response. Large differences at certain frequencies can be very audible in a stereo device, even though the individual responses may be within specification. Sometimes, electrical characteristics such as crosstalk may also be measured. Considerations Before beginning to test headphones, there are two major considerations that need to be taken into account correction curves, and the acoustic seal. These both have an effect of the frequency response. The latter also affects the repeatability of measurements. Coupler Correction Curves Loudspeaker engineers are familiar with the ideal frequency response for a loudspeaker measured in the free field being a flat line (see Figure 1a). For headphones, however, this is not the case. Headphone measurements are taken at what is known as the Drum Reference Point (DRP) a point representing the human eardrum. Figure 2 shows where this is on a Head & Torso Simulator (HATS). If you were to measure the same loudspeaker that produced the flat free-field response curve in Figure 1a at the Drum Reference Point, the frequency response would look like Figure 1b. In other words, for a headphone to sound like a loudspeaker with a flat frequency response, it must produce a frequency response curve like Figure 1b. This frequency response curve is a correction curve, or transfer function that represents the effects of the head, torso, pinna, ear canal and ear simulator. To further complicate matters, different correction curves are applied according to whether your measurements are made in the free field (anechoic room) or diffuse field (reverberation room) (see Figure 3). For the most part, like loudspeaker measurements, the free field is used. Typically, when making measurements, the subtraction of the correction curve from the actual measurement can be carried out in your test software, so that your output frequency response is shown as the familiar straight line. Headphone/Ear Seal Another issue that needs to be addressed when testing headphone is the acoustic seal, or leakage. Realistic headphone measurements (using a HATS or similar) have a certain degree of leakage as the headphone does not fit tightly to the pinna. This has an effect on the frequency response, with a demonstrable loss a) b) Figure 1a and b: Comparison between an ideal loudspeaker freefield measurement and the same measurement in the ear of a head-torso simulation devise DECEMBER

12 at low frequencies (see Figure 4). Although realistic, it affects the repeatability of measurement. In the R&D lab, this is compensated by repeating the measurement multiple times, removing and repositioning the headphone between each measurement and averaging; on the production line different couplers and fixtures are used to offer a more repeatable seal these are discussed in more detail below. High-end speaker units Complete OEM speaker system turnkey solu ons Different Types of Headphones First, before we look at test configurations for headphone testing. Let us look at exactly what we are measuring. Headphone is a broad term, which covers several different designs of product, each with their unique testing challenges. Headphones fall broadly into four categories (see Figure 5): Circumaural (a large SW263WA 10 subwoofer Figure 2: Graphic detail of the DRP using a head-torso simulation device Figure 3: Diffuse and free-field correction curves Exploded view of TW030WA05 tweeter Figure 4: Effect of acoustic leakage on frequency response 12 VOICE COIL

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14 cup that completely surrounds the ear and pinna), Supra-aural (an earpad that sits on the pinna), Earbuds (also known as Supra- Concha), where the transducer rests at the entrance to the ear canal, and In-ear where the sound port sits inside the ear canal. Although the measurements that need to be made are the same for each of these, the fixturing a critical part of the test set-up is different for each type. A Basic Headphone Test Setup Figure 6 shows a headphone test set-up (suitable for all types of headphones) using a PC and soundcard-based measurement system. Although hardware-based systems may, of course, also be used, a soundcard offers more than sufficient accuracy for testing headphones, and such a system is usually less expensive. As you can see, the only part of this setup that will be unfamiliar to those accustomed to loudspeaker measurements is the black Figure 5: Comparison of different headphone types 14 VOICE COIL

15 box that represents a device that simulates the ear (and replaces the microphone in a loudspeaker setup). What s in the Black Box? The equipment in the black box can be a multitude of things, depending on whether you are testing in the R&D lab or on the production line, your budget, and the type of headphone you are testing. Essentially it will be the microphone-containing device you have selected which simulates the human ear with some degree of accuracy, and appropriate fixturing to ensure repeatable results with the particular headphones you are testing. This is perhaps the most complex part of this setup, and the one which poses the most challenges to engineers. In order to select the most appropriate ear simulation device, the first question that must be asked is whether the test should be a realistic simulation of actual use (commonly performed in development) or a highly repeatable test capable of differentiating defective units from good ones (production). When developing a product, it is desirable to have a means of measuring under conditions that the end user will experience. A head-and-torso simulator provides this level of simulation, as it is equipped with artificial ears, which mimic the acoustic characteristics of the human ear, as well as artificial pinnae, which mimic the way a headphone would fit on a real person. The fit of headphones and earphones can vary from person to person and even from one use to another, and can drastically change the user s listening experience. Testing on a head-and-torso simulator (see Photo 1) can reveal this variability between fit and acoustic Figure 6: Analyzer setup for measuring headphone response Photo 1: Testing on a head-and-torso simulator DECEMBER

16 Photo 2: Various pinna couplers used to measure headphone response performance. This lack of repeatability is realistic and useful to understand how fit impacts the sound quality. Engineers will commonly take several measurements and average them to account for it. Head-and-torso simulators are expensive (upwards of $20,000), so some R&D laboratories use less expensive (but with the expected performance trade-offs) alternatives such as cheek and ear simulators, couplers, simplified pinnae, etc. Head-and-torso simulators are not suitable for production line use for two reasons. As discussed, the fit may be slightly different each time, which makes it very difficult to get repeatable results on the production line, and also the cost is prohibitive. This is overcome by designing a product with a known response using simulators (such as the Head & Torso) that accurately replicate a human, and then basing production line testing around ensuring that all products coming off the production line match that ideal product. This means that different test methods can be used. In production and QA it is important to use a fixture that is highly repeatable and can produce consistent results. An acoustic coupler, which is essentially a metal chamber that replicates the ear canal, is most commonly used. Couplers vary significantly in their complexity and cost. The most commonly used production coupler is a 2 cc coupler, which is simply a 2 cubic centimeter cylindrical chamber which is an approximation of the ear canal impedance. More complex (and therefore more expensive) is an IEC 711 coupler which has a multiple internal chambers that more accurately replicate the acoustic impedance of a human ear. Although the characteristics of this coupler are close to the human ear in the lower frequency ranges, above 8 khz it is not well defined. No manufacturer has created a coupler that offers a truly accurate representation of human hearing above 8 khz because human ears vary more at high frequencies. For manufacturers who want to go one step further than a coupler, a pinna with simplified geometry is available. Although not shaped like an ear, it is built to allow some degree of replication of the acoustic leakage that would occur with a real ear. Photo 2 illustrates these devices. Even with the simpler geometry of a coupler, it is still hard to get repeatable results, and most production line applications rely on custom fixturing to offer greater repeatability of mounting for a controlled seal. Usually a fixture is custom built for a specific product to ensure repeatable attachment to the coupler. For circum-aural and supra-aural headphones some sort of clamp is used to apply a consistent pressure, which aids repeatability. Earbuds and in-ear earphones typically use a gasket of some sort to create a seal. This seal produces more accurate low-frequency response and has the added benefit of reducing the influence of ambient noise on the test. 16 VOICE COIL Figure 7: Listen, Inc. SoundCheck screen for headphone response measurement

17 Headphone Tests Now that we understand the test set-up, lets talk about what we typically measure with a headphone. If you are buying a new test system for testing headphones, you should consider what and how you want to test before purchasing, as it has a bearing on the number of inputs and outputs you will need on your soundcard or test system. If you are testing a stereo pair simultaneously, you will need a two-channel soundcard just for the acoustic tests. If you want to also simultaneously measure electrical characteristics such as impedance, you will need four channels. If you already have a two-channel system, you can measure impedance sequentially rather than simultaneously, although it will be a little slower. A typical basic R&D test using a head and torso simulator for a stereo headphone pair would consist of playing a 1/12 octave stepped sine sweep from 20 to 20 khz and measuring the harmonic distortion and fundamental frequency response. Correction curves would compensate for the free-field response from 0 incidence to the nose to the eardrum. Post-processing can then be used to compare the left and right earphone responses and show the difference curve, both for magnitude and phase. With a four-channel analyzer, this test may be expanded with the addition of a couple of reference resistors to measure impedance of the headphones at the same time. Other options for more detailed testing would include measuring intermodulation and difference frequency distortion, or measuring maximum SPL using the distortion level to set the upper limit. Naturally, each company wants to test their products slightly differently, and most test and measurement systems offer the ability to customize tests. A typical production line test would be similar, but a custom compensation curve, based on the coupler and fixturing would need to be applied. On the line, impedance, if measured, would be done simultaneously for speed reasons. Figure 7 shows an example test report for a R&D headphone test carried out in SoundCheck, a soundcard based test system that is used in the R&D lab and on the production line for measuring headphones. Standards IEC : Sound System Equipment Part 7: Headphones and Earphones is probably the most comprehensive standard on headphone testing. It talks about how to classify earphone types (e.g., supra-aural versus supra-concha) describes various couplers and acoustic ear simulators, defines free-field versus diffuse field conditions, and describes how to test headphones. It specifies the standard test level to be 94 dbspl at 500 Hz or 1 mw at the earphone s rated impedance and defines how to measure the rated impedance. A copy of this standard costs approximately $200, and may be purchased from the IEC website ( ch/webstore/webstore.nsf/artnum_pk/43714). Conclusion This article covered the basics of headphone testing, focusing on those issues applicable to all types of headphones. In Part 2, a follow-up to this feature, we will discuss special cases of headphone testing, specifically Bluetooth and USB headphone testing, noise-cancelling headphones, and Max SPL measurements. These are complex subjects requiring the use of different test signals and compensation for time delays, dropouts, and other characteristics inherent to these special types of headphone.vc DECEMBER

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19 Test Bench New Ribbon from FPS and Two 4" Drivers from SB Acoustics By Vance Dickason The samples received for this month s installment of Test Bench included a large format multi-cell ribbon from FPS, the FPS1030M3F1R, plus two 4" ferrite motor drivers from SB Acoustics, the SB12NRX25-4 woofer and the SB12MNRX25-4 midrange. FPS, which stands for Flat Panel Speakers, is a Japanese company founded in 1999 to produce ribbon-based technology. The company manufactures a variety of ribbon transducers from tweeters to large format units intended for use as PA speakers in public venues to pro sound line source stage speakers. Most of their technology is based on a patented (Patent # U.S. 6,963,654 Diaphragm, Flat-Type Acoustic Transducer, and Flat-Type Diaphragm) multiple ribbon cell format titled MMCA for Multi Cell Microtransducer Array (see Photo 1). Figure 1 gives the basic layout of their ribbon transducers with the total ribbon area formed by an array of voice coils with alternating magnetic polarity. You can see how this is specifically applied in the photos of the review subject, the FPS1030M3F1R. Figure 2 illustrates the diaphragm voice coil layout, and Figure 3 depicts the frame and neo magnet layout. Note that the frame photo is for only one side, with another set of magnets located on the opposite side of the frame. In terms of features, the FPS1030 is a large-format ribbon suitable for full-range PA applications or as a mid-range in a multi-way system, or as a wide range in a line source. The ribbon radiating area is about cm, or about 320 cm 2. Power handling is rated at 75-W nominal, sensitivity at 82 db with a frequency range of 90 Hz to 10 khz, and is a nominal 8 Ω. Testing commenced using the LinearX LMS analyzer to measure the impedance as seen in Figure 4. As with most ribbons, the impedance is very flat 7.2 Ω across most of the operating range with a minor resonance at 163 Hz. Next, I mounted the transducer in a small enclosure filled with damping material about the same size as the ribbon frame, so very little baffle reinforcement. Figure 5 gives the on-axis response down to 300 Hz using a 100-point stepped sine wave sweep. The response is quite smooth out to about 10 khz, with a 6-dB shelf between 600 Hz and 1 khz. With a larger baffle or mounted in half-space like an in-wall speaker, the ribbon would perform to a substantially lower frequency. Figure 6 displays the on- and off-axis response in the horizontal plane out to 45 off-axis, while Figure 7 gives the same data in the vertical plane. Given the directivity in the horizontal plane, using the FPS1030 as a midrange in a multi-way system, crossover points of 800 Hz to 5 khz with a narrow baffle would likely work well, and a lower cross point in half-space or with a larger baffle. Figure 8 shows the nearfield response with a low-frequency roll-off of about 3 db at 91 Hz, as specified in the product data. And for the last SPL measurement, Figure 9 gives the two-sample SPL comparison showing these drivers to be well matched throughout the operating range. The final test procedure was to setup the Listen, Inc. SoundCheck analyzer along with the Listen, Inc. SCM ¼" microphone (provided courtesy of Listen, Inc.) to measure the impulse response with the FPS ribbon recess mounted on the test baffle. Importing this data into the Listen Inc. SoundMap software produced the cumulative spectral decay plot (usually referred to as a waterfall plot) given in Figure 10. Figure 11 is Photo 1: The FPS1030M3F1R, a large format multi-cell ribbon, from Flat Panel Speakers (FPS) Figure 1: Graphic layout of the FPS MMCA ribbon configuration Figure 2: Photograph of the voice coil layout in the FPS1030M3F1R Figure 3: Photograph of the frame and magnet layout of the FPS1030M3F1R DECEMBER

20 Ohm 50 Impedance vs Freq dbspl 100 SPL vs Freq Hz K 2K 5K 10K 20K 40K Hz 500 1K 2K 5K 10K 20K Figure 4: Effect of acoustic leakage on frequency response Figure 5: Comparison of different headphone types 100 dbspl SPL vs Freq 100 dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Hz 500 1K 2K 5K 10K 20K Figure 6: Analyzer setup for measuring headphone response Figure 7: FPS FPS1030M31R vertical on- and off-axis frequency response (0 = solid; 15 = dot; 30 = dash; 45 = dash/dot) 100 dbspl SPL vs Freq 100 dbspl SPL vs Freq Hz Figure 8: Nearfield frequency response of the FPS FPS1030M3F1R from 20 Hz to 500 Hz Hz 500 1K 2K 5K 10K 20K Figure 9: FPS FPS1030M3F1R two-sample SPL comparison Figure 10: FPS FPS1030M3F1R SoundCheck CSD waterfall plot Figure 11: FPS FPS1030M3F1R SoundCheck CSD waterfall plot 20 VOICE COIL

21 We re thinking small Seems like all of a sudden, compact arrays are big business. So talk to Celestion about our range of high performance, small-format drivers. AN mm/2" AN mm/2.75" AN mm/3.5" It s another innovation in sound from Celestion. Find us on Facebook

22 a Short Time Fourier Transform (STFT) displayed as a Surface Plot. For the last SoundCheck test procedure, I set the 1-m SPL to 94 db (7.13 V) using a noise stimulus, and measured the 2 nd and 3 rd harmonic distortion at 10 cm, depicted in Figure 12, which was very low throughout the operating range of the device. FPS makes a whole line of MMCA drivers, so check out their entire OEM line of different sized ribbon transducers at www. usfps.com. As most of you are probably aware, SB Acoustics was formed as a partnership between former DST (Vifa, Peerless and ScanSpeak OEM) engineering sales representative David Stephens and Indonesia OEM loudspeaker manufacturer Sinar Baja, with an additional technical partnership with former Vifa/Scan-Speak engineers Ulrik Schmidt and Frank Nielsen, now co-owners of Danesian Audio. Danesian Audio that does all the transducer engineering for SB Acoustics. Voice Coil has featured transducers from SB Acoustics in November 2007 (SB24STC-C000-4 tweeter), December 2007 (SB29NRX " woofer), March 2008 (SB34NRX " woofer), and more recently in the September 2011 (SB26STCN-C000-4 tweeter), and the Figure 12: FPS FPS1030M31R SoundCheck distortion plots Sample Submissions for Test Bench Test Bench is an open forum for OEM driver manufacturers in the industry and all OEMs are invited to submit samples to Voice Coil for inclusion in the monthly Test Bench column. Driver samples can be for use in any sector of the loudspeaker market including transducers for home audio, car audio, pro sound, multi-media, or musical instrument applications. While many of the drivers featured in Voice Coil come from OEMs that have a stable catalog of product, this is not a necessary criterion for submission. Any woofer, midrange, or tweeter an OEM manufacture feels is representative of their work, is welcome to send samples. Contact Voice Coil Editor Vance Dickason to discuss which drivers are being submitted. All samples must include any published data on the product, patent information, or any special information necessary to explain the functioning of the transducer. This should include details regarding the materials used to construct the transducer such as cone material, voice coil former material, and voice coil wire type. For woofers and midrange drivers, please include the voice coil height, gap height, RMS power handling, and physically measured Mmd (complete cone assembly including the cone, surround, spider, and voice coil with 50% of the spider, surround, and leadwires removed). Samples should be sent in pairs and addressed to: Vance Dickason Consulting 333 S. State St., #152 Lake Oswego, OR ( ) vdc@northwest.com 22 VOICE COIL

23 November 2011 (SB26STAC-C000-4 tweeter and MW16R woofer) issues. This month, SB sent me two 4" drivers, one woofer, the SB12NRX25-4 and its 4" midrange version, the SB12MNRX25-4. Features for the SB12NRX and SB12MNRX as you would expect, are nearly identical. Both use a proprietary coated paper and papyrus fiber curvilinear cone and coated paper dustcap, NBR surround, flat Conex spider, a very open proprietary cast frame with a substantially open area below the spider mounting shelf for cooling (this frame is both screwed and glued to the motor assembly), T-yoke, polished edges on the front plate and T-yoke, aluminum shorting ring, 25.4-mm diameter fiberglass non-conduction former, and gold-plated terminals. Both use ferrite magnets that are 20 mm 70 mm, with the SB12MNRX having a secondary 9 mm 60 mm ferrite magnet for additional Bl. I decided to test the SB12NRX (see Photo 2) woofer version first and began analysis using the LinearX LMS analyzer and VIBox to create both voltage and admittance (current) curves with the driver clamped to a rigid test fixture in free-air at 0.3 V, 1 V, 3 V, and 6 V. As has become the protocol for Test Bench testing, I no longer use a single added mass measurement and instead used actual measured mass, but the manufacturers measured Mmd data. At this point the 6-V curves were discarded as being too non-linear for the curve fitting algorithm to resolve. Next, the remaining six 550-point stepped sine wave sweeps for each SB12NRX sample were post-processed and the voltage curves divided by the current curves (admittance) to derive impedance curves, phase added by the LMS calculation method, and along with the accompanying voltage curves, imported to the LEAP 5 Enclosure Shop software. Since most Thiele-Small data provided by OEM manufacturers is being produced using either a standard method or the LEAP 4 TSL model, I additionally created a LEAP 4 TSL model using the 1-V free-air curves. The complete data set, the multiple voltage impedance curves for the LTD model (see Figure 13 for the 1-V free-air impedance curve) and the 1-V impedance curve for the TSL model were selected in the transducer derivation menu in LEAP 5 and the parameters created for the computer box simulations. Table 1 compares the LEAP 5 LTD and TSL data and factory parameters for both of SB samples. LEAP parameter calculation results for the SB were fairly similar to the factory TS parameters, with a higher Vas and lower SPL Photo 2: The SB12NRX25-4, a 4" woofer from SB Acoustics Ohm Impedance vs Freq 1 10 Hz K 2K 5K 10K 20K Figure 13: SB Acoustics SB12NRX25-4 woofer free-air impedance plot for the measured data compared to the factory data. While TSL parameters were closer to the factory data (except the Vas and SPL as mentioned), I proceeded to put together computer enclosure simulations using the LEAP LTD parameters for Sample 1. I set up two box simulations, one sealed and one vented. This produced a 0.12 ft 3 sealed box with 50% fiberglass fill material, and a 0.20 ft 3 Qb 3 vented enclosure with 15% fiberglass fill material and tuned to 48 Hz. Figure 14 gives the outcome for the SB Acoustics SB12RNX25-4 in the sealed and vented boxes at 2.83 V and at a voltage level sufficiently high enough to increase cone excursion to Xmax + 15% (5.75 mm for the SB12NRX). This generated a F 3 frequency of 79 Hz with a box/driver Qtc of 0.69 for the 0.12 TSL model LTD model Factory sample 1 sample 2 sample 1 sample 2 Fs 47.0 Hz 48.1 Hz 46.4 Hz 47.4 Hz 55 Hz Revc Sd Qms Qes Qts Vas 8.95 ltr 8.53 ltr 9.25 ltr 8.85 ltr 5.6 ltr SPL 2.83 V 85.1 db 85.2 db 84.2 db 84.3 db 87.5 db Xmax 5.0 mm 5.0 mm 5.0 mm 5.0 mm 5.0 mm Table 1: SB Acoustics SB12NRX25-4 Woofer PACIFIC AUDIO CONSULTING Audio supply chain from raw materials to finished product. Engineering design, test, sourcing and business advice. PO Box 3252, Redmond, WA rob.pacific.audio@gmail.com DECEMBER

24 t 3 sealed enclosure (perfect for a home theater satellite and meeting the requirements for THX certification) and 3 db = 61 Hz for the 0.20 ft 3 vented simulation. Increasing the voltage input dbspl SPL vs Freq to the simulations until the maximum linear cone excursion was achieved produced 99 db at 10 V for the sealed enclosure simulation and 100 db with the same 10-V input level for the larger vented box (see Figures 15 and 16 for the 2.83-V group delay curves and the 10-V excursion curves). Note that I left the input at 10 V since the Xmax was being exceeded at 40 Hz. As with all vented enclosures, power handing can be significantly increased by adding a steep high-pass filter approximately one octave lower than the F 3. Klippel analysis for the SB Acoustics 4" woofer (our analyzer is provided courtesy of Klippel GmbH) performed by Hz K Figure 14: SB Acoustics SB12NRX25-4 computer box simulations (black solid = sealed 2.83 V; blue dash = vented 2.83 V; black solid = sealed 10 V; blue dash = 10 V) 20m Sec Time vs Freq 15m 10m 5m Figure 17: Klippel Analyzer Bl (X) curve for the SB Acoustics SB12NRX Hz K Figure 15: Group delay curves for the 2.83-V curves in Figure 14 20m M Excursion vs Freq 10m 5m 2m 1m 500u 200u 100u 10 Hz K Figure 16: Cone excursion curves for the 10-V curves in Figure 14 Figure 18: Klippel Analyzer Bl symmetry range curve for the SB Acoustics SB12NRX25-4 REVOLUTIONARY DRIVER thermoformed strand-oriented polypropylene cone cast aluminium basket copper sleeve with shorting ring copper plated dust cap aluminium former XBL TM leading multigap motor RevSurround TM allows greater, more linear stroke For OEM inquiries please contact: 24 VOICE COIL VWR126X Figure 19: Klippel Analyzer mechanical stiffness of suspension Kms (X) curve for the 1 SB Acoustics SB12NRX25-4

25 Pat Turnmire, Red Rock Acoustics (author of the SpeaD and RevSpeaD software) produced the Bl(X), Kms(X) and Bl and Kms symmetry range plots given in Figures This data is extremely valuable for transducer engineering, so if you don t own a Klippel analyzer and would like to have analysis done on a particular driver project, Red Rock Acoustics can provide Klippel analysis of most any driver for a nominal fee of $100 per unit. (For contact information, visit the Red Rock Acoustics website at The Bl(X) curve for the SB12NRX (see Figure 17) is moderately broad and symmetrical with a small rearward (coil-in) offset Looking at the Bl symmetry plot (see Figure 18), this curve shows a coil inward offset at the rest position of about 1.78 mm that decrease to about 0.78 mm inward offset at the physical Xmax (5 mm) and then stays constant throughout the remaining operating range of the driver, suggesting that the voice coil is not located at magnetic center. With proper assembly jigs, a manufacturer should be able to hole a ±0.25 mm tolerance at the magnetic center. This problem is not what you would call huge, and it mostly results in somewhat increased 2 nd harmonic distortion (which tends to be categorized as pleasant by listeners), but is fairly common. If you go through the cumulative review in Test Bench, this occurs fairly often in samples I receive. Figures 19 and 20 depict the Kms(X) and Kms symmetry range curves for the SB 4" woofer. The Kms(X) curve has some minor asymmetry beyond about 4 mm of excursion. There is no offset at the rest position, and starting at about 2 mm, there is a forward (coil-out) offset increasing to about 0.5 mm at the Figure 20: Klippel Analyzer Kms symmetry range curve for the SB Acoustics SB12NRX mm Xmax position. Displacement limiting numbers calculated by the Klippel analyzer for the SB12NRX were 82% Bl = 5.0 mm and for 75% Cms minimum was 4.3 mm, which means that for the SB 4" woofer, the compliance is the most limiting factor for prescribed distortion level of 10%. Figure 21 gives the inductance curves Le(X) for the SB12NRX. Inductance will typically increase in the rear direction from the zero rest position as the voice coil covers more pole area, and although that is what you see for this driver, the variation in inductance across the operating range is only about 0.05 mh, which is a function of the aluminum shorting ring. Next, I mounted the SB12NRX25-4 woofer in an enclosure DECEMBER

26 100 dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Figure 21: Klippel Analyzer Le(X) curve for the SB Acoustics SB12NRX25-4 Figure 22: SB Acoustics SB12NRX25-4 on-axis frequency response 100 dbspl SPL vs Freq 100 dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Figure 23: SB Acoustics SB12NRX25-4 on- and off-axis frequency response Hz 500 1K 2K 5K 10K 20K Figure 24: SB AcousticsSB12NRX25-4 two-sample comparison 26 VOICE COIL

27 Figure 25: SB Acoustics SB12NRX25-4 SoundCheck distortion plots DECEMBER

28 which had a 13" 6" baffle (filled with foam damping material) and then measured the driver on- and off-axis from 300 Hz to 20-kHz frequency response at 2.83 V/1 m using the LinearX LMS analyzer set to a 100-point gated sine wave sweep. Figure 22 depicts the SB12NRX s on-axis response indicating a smoothly rising response to about 5 khz, with the typical 3 to 4 db peaking centered on 1.2 khz, and a couple of breakup modes centered on 7 khz and 10 khz. Figure 23 displays the on- and off-axis frequency response at 0, 15, 30, and db at 30 with respect to the on-axis curve occurs at 4.5 khz, so a cross point in that vicinity or lower should be optimal. And finally, Figure 24 gives the two-sample SPL comparisons for the 4" SB Acoustics driver, showing a very close match throughout the operating range. For the remaining group of test, I used the Listen, Inc. SoundCheck analyzer (courtesy of Listen, Inc.) to measure distortion and generate time frequency plots. For the distortion measurement, the woofer was mounted rigidly in free-air, and the SPL set to 94 db (6.85 V) at 1 m using a noise stimulus, and then the distortion measured at with the Listen, Inc. microphone placed 10 cm from the dust cap. This produced the distortion curves shown in Figure 25. I then used SoundCheck to get a 2.83 V/1-m impulse response for this driver and imported the data into Listen, Inc. s SoundMap Time/Frequency software. The resulting CSD waterfall plot is given in Figure 26 and the Wigner-Ville (for its better low-frequency performance) plot in Figure 27. With analysis on the first SB woofer accomplished, I per- formed an identical group of tests on the SB Acoustics 7" SB12MNRX (see Photo 3). As before, the LinearX LMS analyzer and VIBox were employed to create both voltage and admittance (current) curves. This test is accomplished with the driver clamped to a rigid test fixture in free-air with sweeps taken at 0.3 V, 1 V, 3 V, and 6 V. Like the SB12NRX, the 6-V curve was too nonlinear and was discarded, which is interesting considering the SB12MNRX has on 2.25 mm Xmax compared to the 5-mm Xmax of the woofer version. The remaining six 550-point stepped sine wave sweeps for each SB12MNRX sample were post-processed and the voltage curves divided by the current curves (admittance) to create impedance curves, phase added using LMS calculation method, and along with the accompanying voltage curves, saved to the LEAP 5 Enclosure Shop software. In addition to the LEAP 5 LTD model Figure 26: SB Acoustics SB12NRX25-4 SoundCheck CSD waterfall plot Vance Dickason Consulting Loudspeaker Product Development Vance Dickason Consulting has been developing award winning products for numerous high profile brand names for over 20 years experience that s hard to find! Add to that an available design team that includes some of the best transducers engineers, industrial designers and marketing experts I know of in the industry and you have a winning combination that would cost well over $750,000 a year to keep in house. With extensive experience in high-end off-wall, in-wall, on-wall, ceiling and subwoofer products plus close relationships with some of the worlds best speaker OEM s and you have a combination of services that will accelerate your next product lineup. We have all the best toys (Klippel, LEAP 5, LMS, CLIO, MLSSA, LSPCad, FEA), so whether its multimedia, car audio, MI, Pro, two-channel or Home Theater (including THX ), VDC has the solutions. Figure 27: SB Acoustics SB12NRX25-4 SoundCheck Wigner-Ville plot 28 VOICE COIL Tel: (503) vdc@northwest.com

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30 results, I also created a LEAP 4 TSL model set of parameters using just the 1-V free-air curves. The final data set, which includes the multiple voltage impedance curves for the LTD model (see Figure 28 for the 1-V free-air impedance curve) and the 1-V impedance curve for the TSL model, were selected and the parameters created in order to perform the computer box simulations. Table 2 compares the LEAP 5 LTD and TSL data and factory parameters for both of SB Acoustics 4" midrange samples. LEAP parameter calculation results for the SB12MNRX midrange, like the woofer version, only moderately close to the SB factory data, again with the measured data yielding a closer match with the TSL data except for the higher Vas and lower SPL. I proceeded however, to set up computer enclosure simulations using the LEAP LTD parameters for Sample 2. I set up two box simulations, one sealed and one vented. For the closed box simulation I used a 0.16 ft 3 enclosure with 50% fiberglass fill material, and for the vented box, a 0.15 ft 3 Qb 3 vented enclosure with 15% fiberglass fill material and tuned to 61 Hz. Figure 29 displays the results for the SB12MNRX in the sealed and vented boxes at 2.83 V and at a voltage level sufficiently high enough to increase cone excursion to Xmax + 15% (2.6 mm for the SB12 midrange). This resulted in a F 3 = 106 Hz with a box/driver Qtc of 0.69 for the 0.16 ft 3 sealed enclosure and a 3 db = 76 Hz for the 0.15 ft 3 vented simulation. Increasing the voltage input to the simulations until the maximum linear cone excursion was reached generated 97 db at 6 V for the sealed enclosure simulation and 97.3 db with the same 6-V input level for the larger vented box (see Figures 30 and 31 for the 2.83-V group delay curves and the 6-V excursion curves). As with any midrange transducer, the box size is usually only a method to locate the resonance as low in frequency as possible to facilitate a passive high-pass section of a band-pass filter. Power handling with such a filter is substantially increased from the non-filter simulation above. Klippel analysis for the SB Acoustics 4" midrange produced the Bl(X), Kms(X) and Bl and Kms Symmetry Range plots given in Figures 32 to 35. The Bl(X) curve for the SB12MNRX (see Figure 32) is fairly narrow, but very symmetrical, about what you expect from a small Xmax midrange. For all practical purposes, there is zero offset indication, so about as good as it ever gets. Figures 34 and 35 give the Kms(X) and Kms symmetry Range curves for the SB Acoustics 4" mid. The Kms(X) curve, Photo 3: The SB12MNRX, a 7" driver from SB Acoustics Impedance vs Freq Ohm Hz K 2K 5K 10K 20K Figure 28: SB Acoustics SB12MNRX25-4 free-air impedance plot TSL model LTD model Factory sample 1 sample 2 sample 1 sample 2 Fs 57.3 Hz 59.5 Hz 55.2 Hz 57.4 Hz 58 Hz Revc Sd Qms Qes Qts Vas 6.88 ltr 6.37 ltr 7.46 ltr 6.90 ltr 5.5 ltr SPL 2.83 V 86.5 db 86.8 db 85.6 db 86.3 db 88.5 db Xmax 2.25 mm 2.25 mm 2.25 mm 2.25 mm 2.25 mm Table 2: SB Acoustics SB12MNRX25-4 midrange 105 dbspl SPL vs Freq Hz K Figure 29: SB Acoustics SB12MNRX25-4 computer box simulations (black solid = 2.83V; blue dash = 2.83 V; black solid = V; blud dash = 6 V) 30 VOICE COIL

31 20m Sec Time vs Freq 20m M Excursion vs Freq 10m 15m 5m 2m 10m 1m 500u 5m 200u 0 10 Hz K Figure 30: Group delay curves for the 2.83-V curves in Figure u 10 Hz K Figure 31: Cone excursion curves for the 6-V curves in Figure 29 Figure 32: Klippel Analyzer Bl (X) curve for the SB Acoustics SB12MNRX25-4 Figure 33: Klippel Analyzer Bl symmetry range curve for the SB Acoustics SB12MNRX25-4 FX100 Audio Analyzer offers proven PureSound speaker testing technology Proven PureSound technology For the most reliable detection of different defect types. Supports defects testing across all installed analyzer channels. Modular Analyzer architecture Customize your speaker test system by choosing the number of analysis channels, built-in impedance and DCresistance measurements, switchers etc. Cost efficiency System costs are controlled with modular configurations matched to specific applications. Maximum test speed Very fast glide sweep technology measures all quality parameters from a single stimulus within a fraction of a second. FX-Control software Powerful and complete system control suite supports flexible GUI designs, built-in limits handling and sequenced measurements. NTi Audio AG Liechtenstein info@nti-audio.com NTI Americas Inc. Portland, Oregon, USA americas@nti-audio.com NTI China NTI Japan Suzhou, Beijing, Shenzhen Tokyo, Japan china@nti-audio.com japan@nti-audio.com DECEMBER

32 Figure 34: Klippel Analyzer mechanical stiffness of suspension Kms (X) curve for the SB Acoustics SB12MNRX25-4 Figure 35: Klippel Analyzer Kms symmetry range curve for the SB Acoustics SB12MNRX dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Figure 36: Klippel Analyzer Le(X) curve for the SB Acoustics SB12MNRX25-4 Figure 37: SB Acoustics SB12MNRX25-4 on-axis frequency response Setting the standard for high performance anechoic chambers for more than five decades... ECKEL ANECHOIC CHAMBERS for product testing for research studies...providing the necesary acoustic environment for obtaining reliable, precise measurements Building on a tradition of excellence and innovation in acoustic test facilities, Eckel now offers an expanded range of quality-engineered anechoic chambers and hemi-anechoic chambers to meet virtually any testing range requirements with low frequency cutoffs down to 40 Hz... and any testing space needs from small, standard portable enclosures to the largest, customengineered double-walled acoustic structures. Eckel s modular attenuating structures have guaranteed performance and incorporate numerous state-of-the-art features: choice of four types of wedge linings, including the EMW perforated metallic anechoic wedge which combines outstanding performance, long-term acoustic integrity, and light weight special track system for efficient installation of wedges unique cable floor system sound attenuating doors instrumentation sleeves and supports ventilation lighting and power systems. All of Eckel s acoustic test facilities meet ISO and ANSI standards and provide cost-effective solutions to achieving a superb environment for research in acoustics and psycho-acoustics, as well as for acoustic testing in fields such as audio, appliances, computers, industrial components, and consumer electronics. And Eckel offers integrated design and engineering services and turnkey capability. For full details, contact: ECKEL INDUSTRIES, INC., Acoustic Division 155 Fawcett Street, Cambridge, MA Tel: eckelvc@eckelusa.com 32 VOICE COIL

33 like the Bl curve, is very symmetrical with practically no offset, indicating a lot of design integrity. Displacement limiting numbers calculated by the Klippel analyzer for the SB12MNRX were 82% Bl = 3.3 mm (1.05 mm greater than the physical Xmax!) and for 75% Cms minimum was 4.0 mm, which means that for the SB12MNRX woofer, the Bl is the most limiting factor for prescribed distortion level of 10%. Figure 36 gives the inductance curves Le(X) for the SB12MNRX. This also very similar to the SB12NRX, with a very small inductance change across the operating range of 0.03 mh, indicating that the aluminum shorting ring does a good job of controlling inductance. With the Klippel testing accomplished, I mounted the SB12MNXR25-4 midrange driver in an enclosure which had a 13" 6" baffle and was filled with foam damping material and then measured the driver both on and off-axis from 300 Hz to 20 khz frequency response at 2.83 V/1 m using a 100-point gated sine wave sweep. Figure 37 depicts the SB12MNRX s onaxis response displaying a very smooth rising response to about 6 khz, with a 2 db peak centered on 1.2 khz and breakup mode centered on 8 khz, and as you would expect, very similar to the SB12NRX. Figure 38 has the on and off-axis frequency response at 0, 15, 30, and db at 30 with respect to the on-axis curve occurs at 4.5 khz, so a 4.5 khz to 5 khz crossover frequency would be appropriate for this SB driver. And finally, Figure 39 gives the two-sample SPL comparisons for the 4" SB midrange driver, showing a less than 0.5 db match up to 4 khz. For the last body of testing on the SB 4" mid, I again fired up the Listen, Inc. SoundCheck analyzer (courtesy of Listen, Inc.) dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Figure 38: SB Acoustics SB12MNRX25-4 on- and off-axis frequency response dbspl SPL vs Freq Hz 500 1K 2K 5K 10K 20K Figure 39: SB Acoustics SB12MNRX25-4 two-sample SPL comparison DECEMBER

34 Figure 40: SB Acoustics SB12MNRX25-4 SoundCheck distortion plots and SCM microphone and power supply to measure distortion and generate time frequency plots. Setting up for the distortion measurement again consisted of mounting the woofer rigidly in free-air, and the SPL set to 94 db (5.27 V) at 1 m using a noise stimulus (SoundCheck has a software generator and SPL meter as two of its utilities), and then the distortion measured with the SCM microphone placed 10 cm from the dust cap. This produced the distortion curves shown in Figure 40. Finally, I employed the SoundCheck analyzer to get a 2.83 V/1 m impulse response for this driver and imported the data into Listen, Inc. s SoundMap Time/Frequency software. The resulting CSD waterfall plot is given in Figure 41 and the Wigner-Ville (for its better low-frequency performance) plot in Figure 42. For more information, visit the SB website at VC Figure 41: SB Acoustics SB12MNRX25-4 SoundCheck CSD waterfall plot Figure 42: SB Acoustics SB12MNRX25-4 SoundCheck Wigner- Ville plot 34 VOICE COIL

35 Spotlight MoTIV Loudspeaker Magnetics Modeler By Rob Baum, Pacific Audio Consulting Speaker engineers began to move from the era of trial-anderror speaker design when Novak, Thiele, and Small wrote papers that electrically modeled electro-acoustic performance. Much of that key work was explained by Vance Dickason s ubiquitous Loudspeaker Design Cookbook, which is on almost every speaker engineer s desk around the world. Since the LDC was first published in 1975, a wide array of modeling software has come and gone from the market, most of it for enclosure design. However, the most significant advance has been the transducer modeling programs such as Red Rock Acoustics SpeaD and RevSpeaD software, and LOUDSoft s FINEMotor. MoTIV from Dyne Analytics, is probably the most recent addition to this transducer modeling software category, and includes FEA as part of its modeling platform. At its heart, MoTIV is a loudspeaker, motor-design oriented, advanced, task-specific pre- and post-processor FEA calculation engine which derives its core results from that FEA. However, MoTIV also has extensive mathematical models that allow the effects of many changes to be estimated instantly and to guide the design. Where possible, these changes are presented immediately as the changes are made, but also updated with true FEA results when the next simulation is run. Thus, the designer is free to make numerous adjustments towards a desired result without requiring extensive FEA calculations, and then update with real FEA results at their discretion. Estimated values are replaced with FEA results as calculations are run. The designer is always shown the most recent and upto-date information available. The pre-processor in MoTIV is presented with an interface that uses just three forms (lists) to be filled out and a graphical view. That s all that is required to set up and run the FEA calculation engine. Data that must be entered in order to define a typical ring motor design is broken into four categories: motor definition (top plate, bottom plate, magnet, and pole dimensions plus magnet material description); inductance control (pole sleeve, upper shorting ring, gap shorting ring, and lower shorting ring dimensions); and voice coil (ID, wire diameter, wire material, layers, winding width, and voice coil offset). Typical dimensions and material specifics are entered into the forms, and the visual model instantly reflects those updates. Conflicts in the model are shown as soon as encountered, giving you instant feedback of problems with the definitions. Only when all parts are properly entered will an FEA calculation be available. Note that MoTIV does both Ring Style (magnet outside the voice coil) and Cup Style (magnet inside the voice coil) motors. Once the design is entered, MoTIV displays a series of live graphs that present the data in a variety of ways, including a graphic motor cutaway, flux profile, distortion vs. excursion, Bl vs. excursion, B field vs. position, magnetic load lines, in box response, Le vs. frequency vs. excursion, and TS parameters (see Figures 1 and 2). The user gets instant feedback of these critical performance metrics as you adjust temperature, voice coil dimensions, and other parameters. The software also includes a built-in box modeling utility so the user can imme- b) Figure 1: MoTIV loudspeaker magnetic modeler graph screens DECEMBER

36 Figure 2: MoTIV loudspeaker magnetic modeler main screen diately see the results of your design in its intended application. To find an optimal design, the user can run up to three concurrent designs simultaneously and view the results in parallel. Every MoTIV file contains a history of what was changed, and every change can be annotated, to keep track of what was changed and why. This traceability is important for long-term product viability, and to pass on the complete documentation to new engineers. When the design is done, MoTIV can generate a complete report of the design, including all dimensions, graphs, and parameters, for archiving and/or distribution to clients or manufacturers. Other features include a units conversion utility, a multi-disc magnet calculator (to design motors using a ring of smaller magnets, rather than one large magnet) and a built-in reverse Thiele/Small parameter calculator with real-time feedback as well as a Xmag calculator (enter a desired SPL and frequency for your T/S parameters and the software outputs exactly how much excursion is required (see Figure 3). For more, visit the website at com. VC Figure 3: MoTIV TS parameter Wizard menu 36 VOICE COIL

37 MoTIV Motor Design Modeling ANNOUNCING THE DEBUT OF VIBRĀT Expert Cone, Dome, and Suspension FEA Modeling Test Drive VIBRĀT at 2012 CES and ALMA EASY TO LEARN. EASY TO USE. ACCURATE. COST EFFECTIVE. DYNE ANALYTICS Hong Kong

38 Industry Watch By Vance Dickason Audio Pioneer Dies at Age 94 It is with regret that Voice Coil must report the passing of one of the loudspeaker industry s true pioneers. Edgar M. Villchur whose invention of a small loudspeaker that could produce Edgar M. Villchur ( ) deep, rich bass opened the high-fidelity music market in the 1950s to millions of everyday listeners died on October 17, 2011 at his home in Woodstock, N.Y. He was 94. In the Hi-Fi News 50 th anniversary issue in 2006, the magazine ranked him No. 1 among the 50 most important audio pioneers. Many others, such as John Atkinson, the editor of Stereophile magazine, also credits him with bringing hi-fi into the home. Such is the general public s knowledge of Mr. Villchur, but those of us actively involved in designing loudspeakers realize the tremendous impact of his work in developing sealed-box loudspeakers. The following was published in the October 17, 2011 edition of the New York Times: Edgar Marion Villchur was born in Manhattan on May 28, 1917, the only child of Mark and Mariam Villchur, who had immigrated from Russia. His father was editor of a Russianlanguage newspaper, his mother a biologist. It was his service in World War II that sparked Mr. Villchur s fascination with sound and electronics. He had graduated from City College in Edgar M. Villchur 1938, and then earned a master s degree in education there two years later. But within a year he was drafted into the Army Air Forces and was trained as an electronics technician. For most of the next five years, while rising to captain, he was responsible for his squadron s radio operations in the Pacific. After the war Mr. Villchur opened a radio shop in Greenwich Village, making repairs and building custom hi-fi sets. He also taught a course in sound reproduction at New York University. Mr. Villchur married Rosemary Shafer in Besides his wife and daughter, he is survived by a son, Mark, of Boston. The Villchurs moved to Woodstock in In his basement, Mr. Villchur began testing his notion of a sealed-cabinet loudspeaker. One day in spring 1954, speaking to his acoustics class at N.Y.U, he hinted at his idea. One student, Henry Kloss, stayed after class, eager to learn more. Soon, student and teacher were in Mr. Villchur s 1938 Buick, headed to Woodstock. 38 VOICE COIL

39 In Mr. Villchur s basement workshop, they listened to the copious low-frequency tones on an LP recorded by the renowned organist E. Power Biggs. Mr. Kloss had a loft in Cambridge, Mass., where he was already building mail-order cabinets for Baruch-Lang speakers. It became the first headquarters for Acoustic Research. Mr. Kloss, who died in 2002, is credited with designing the production process for the AR-1 speaker and its successors, the AR-2 and the AR-3, which combined Mr. Villchur s woofer and tweeter models. Among Mr. Villchur s duties was promoting the products. In the early 1960s, he sponsored live vs. recorded concerts around the country, including one in a recital room at Carnegie Hall and another at Grand Central Terminal. At the concerts, a string quartet would play a piece of music, then mime it as parts of a recording by the same quartet played through a pair of AR-3 speakers. The listeners were rarely able to detect the switchovers. Mr. Villchur was president of Acoustic Research until After being bought by a series of manufacturers, the company went out of business in Its brand name was bought by the Audiovox Corporation. Soon after leaving Acoustic Research, Mr. Villchur started the Foundation for Hearing Aid Research in Woodstock, where he developed a prototype of the multichannel compression hearing aid that has become an industry standard. If you have never seen Edgar talk about his favorite subject, transducers, go to the Audio Engineering Society s website oral history section ( for a short presentation Mr. Villchur made in February He will be missed. Steve Jobs Remembered It would be impossible for Voice Coil not to also acknowledge the passing of Steve Jobs. While Steve s contributions were not specific to loudspeakers, his effect upon the consumer electronics industry was unparalleled. For our industry, you only have to look at the recent proliferation of ipod dock desktop loudspeakers to see the tremendous impact that he had. Sadly, Steve s life was cut short at 56, so we will never know what electronic marvels he would have helped usher into the world. Like Edgar, he will be missed. KEF Celebrates 50 Years British audio brand KEF celebrated its 50 th anniversary with parties worldwide, including a party at the British consul-general s official residence. About 100 KEF dealers, reps, employees, and customers attended the event, hosted by consul-general Danny Lopez, who lauded KEF for exemplifying innovation. In speaking to guests, KEF America President Alec Chanin noted that in the home audio industry, not a lot of companies have had this long a run. Besides doing its own design and engineering, he said, KEF still invests in pure research. To continue the celebration, in February KEF will launch its second 50 th anniversary product following the launch earlier this year of the $29,999/pair KEF Blade, which was played at the event and was the first product launched by the company SMALL and LOUD speakers Increase Output Shrink Size Improve Performance! DECEMBER

40 to celebrate its anniversary. KEF is promoting its 50 th anniversary message in print and online ads that focus on its heritage and feature a series of famous past products, said KEF America Marketing Manager Stephanie Scola. KEF celebrates its 50 th anniversary On September 29, the company will launch a website, to highlight the top 50 products from its 50 years in business. A commemorative hardcover book outlining KEF s history has also been published and became available on Amazon in mid-october at $ Happy Birthday KEF! HTSA Experiences Resurgence The Home Technology Specialists of America (HTSA) is enjoying a resurgence of its high-end audio, automation and home-networking businesses, the buying group s senior executives reported. Executive committee members Jon Robbins, principal of HiFi House, and Brian Hudkins, owner of Gramophone, maintain that many of HTSA s 56 member integrators, A/V dealers and custom installers have seen a significant bump in those categories, as customers elect to invest in their current homes rather than purchase new ones. The group, now in its 16 th year, gathered for its annual fall Pump Up meeting, the first without former executive director Richard Glikes, who resigned unexpectedly in August. HTSA began interviewing 40 VOICE COIL

41 potential successors during last month s CEDIA Expo and has narrowed a 12-person field down to two candidates. A final decision is expected shortly, and the new executive director will make his formal debut at International CES in January. PMI Appoints New Chief Engineer Performance Media Industries (PMI) announces the appointment of Manny LaCarrubba as chief engineer. With over 20 years in the professional audio space, Manny LaCarrubba brings to PMI extensive experience in acoustics, music production, audio technology, and business acumen. Leading PMI s engineering team, LaCarrubba will be responsible for expanding and improving its methodologies and technologies for the engineering and specification of high-end residential and commercial spaces, recording studios, and venues. LaCarrubba has worked as a recording engineer in the music industry and as a consulting technology engineer to the semi-conductor industry specializing in noise and vibration control. In the late 1990s, he founded Sausalito Audio to commercialize patents related to loudspeaker design, and to produce advanced audio and architectural loudspeaker systems for custom installation. For 10 years, LaCarrubba was a staff and chief engineer at the famed Sausalito recording studio, The Plant. His music engineering credits include tracks and albums for Santana, Michael Bolton, Celine Dion, Kenny G, Mariah Carey, and many more. He also designed some of The Plant s seminal recording rooms. LaCarrubba has served as an acoustical consultant providing services in room design, acoustical treatments, electrical and audio wiring design, sound transmission control, and custom furniture design. His unique perspective on architectural acoustics comes from many years of study and work with loudspeaker/room interactions, combined with music production in rooms he has designed with loudspeakers of his own design. LaCarrubba earned a bachelor of science degree in Tonmeister Studies from State University of New York at Fredonia. He holds several patents related to loudspeaker engineering, all of which have been integrated into commercial products manufactured by Bang & Olufsen of Denmark. LaCarrubba is a member of the Audio Engineering Society (AES). He is featured in videos produced by Secrets of the Pros where he teaches studio design, acoustics, and recording and mixing techniques. He will be based in PMI s Novato, CA headquarters. Recent Innovations Showcased Senior executives and product developers for Legrand, Vantage, and BTicino hosted an intimate press tour of an exclusive luxury residence in Manhattan s Tribeca neighborhood that showcases whole-house AV and lighting control, as well as a demo of Legrand s airqast wireless speaker system. In addition to overviewing products from all three brands and showing how they look together in action, airqast was prominently demonstrated. Executives were very enthusiastic about the Wi-Fi speaker system, which provides a mobile interface for users to choose music, adjust volume, create playl- Mini TA Wx2 Class-D Amplifier Good sound quality, compact size, beautiful looking 6N11 24V Hybrid Headphone Amplifier Unique design, powered by single 24V, excellent performance Used Wima 3.3uf/630v HiFi Capacator Many other used/new caps available at super low price 6F3 2.5Wx2 Tube Audio Amplifier Mini size, extremely well built, ideal gift for X mas DECEMBER

42 The Coolest Nerds Work at Monster!! Monster, the world s leader in high-end consumer electronics accessories, is growing and expanding rapidly. We want to talk to technically savvy product development A Players to join our Team! Product Engineers Monster is looking for experienced Product Engineers with a successful track record of designing and deploying innovative consumer electronics accessories. The successful candidate will demonstrate a thorough understanding of a structured product lifecycle management process utilizing US design resources and collaborative supply chain analytics to bring high quality consumer electronics products to market on time and at the right price. Product Area Managers (PAM) Monster is looking for product category experts who are innovators, who can be market gurus, partner with sales, project managers and business leaders. You are the subject matter expert on big-box retail channels, specialized channels, independent retailers, distributors, sales and marketing strategies. You re in charge of leading product development by getting the right product at the right price to market on-time, with the proper sell-in and sell-through support, with responsibility for worldwide profitability. For more information, please visit

43 ists, and stream IP radio from their smartphones and tablets. The CEDIA channel had an initial glimpse of airqast recently at EXPO in Indianapolis, but the demo was much more impactful without the tradeshow buzz soaking up the sound. Consisting of two speakers with 40 W per channel, the sound quality exhibited a strong range in volume and came across without any noticeable distortion on the high end. The speakers are set up for use with a subwoofer that is sold separately. CEA Standardizes Terms The Consumer Electronics Association (CEA) have announced the publication of CEA , Wireless Power Glossary of Terms. The standard, defined by CEA s Wireless Power Subcommittee, addresses system components in order to facilitate widespread deployment of interoperable wireless power systems. It is the first of several planned standards designed to advance wireless charging technology, changing how consumers charge their devices. Wireless power technology streamlines the process of charging portable consumer electronics devices by eliminating the need to physically connect the device and the charger. CEA is available for purchase from IHS at com. CEA s Wireless Power Subcommittee is also working on standards for highly resonant (also known as loosely coupled ) wireless power transfer, tightly coupled wireless power systems, and energy-efficiency measurements for wireless power systems. Companies interested in participating in this CEA work can visit standards.ce.org and join the R6.3 Wireless Power Subcommittee and its working groups. For more information, contact Dave Wilson at dwilson@ce.org, or Harman's Sales Rise Harman International Industries reported higher net sales and higher net profits in its fiscal first quarter, ended September 30. Net sales for the first quarter were $1.051 million, an increase of 26% compared with the same period last year. Excluding foreign currency translation, net sales increased by 19%. Net income was $48 million, up from the prior year s $27 million. Operating income was $74 million, compared with $43 million in the same period last year. During this quarter, all three of the company s divisions reported higher sales. In the infotainment division, net sales were $603 million, up from the prior year s $446 million. Operating income was $47 million, up from $8 million. Harman attributed higher sales to pent-up demand from the Japan tsunami and earthquake and continued growth in BRIC countries. In its lifestyle division, sales were up 19% to $300 million compared with last year due to the same factors in the infotainment division, but operating income was down $3 million to $26 million. Profits were down due to higher costs of neodymium magnets. In the professional division, net sales were $148 million, up $8 million, while operating profit was down $6 million from the prior year s quarter to $19 million. Japan's Earthquake Impacts Overseas Partners Rockford Corporation boosted net income and gross margins in its fiscal third-quarter and year-to-date periods on a 0.7% decline in third-quarter sales and a 12.3% rise in year-to-date sales. Sales DECEMBER

44 fell in the third quarter primarily because of declining revenue from Japanese automakers whose supply chains were interrupted by the Japan earthquake earlier this year, the company said. Net sales for the three months, ended September 30, were down 0.7% to $14.2 million compared with the year-ago $14.3 million. Net sales for the first nine months of the fiscal year rose 12.3% to $47.8 million compared with a year-ago $42.6 million. Net income for the third quarter rose 71% to $1.2 million from a year-ago $700,000, and for the nine-month period, net income rose 68% to $4.2 million from a year-ago $2.5 million. As percent of net sales, gross margins increased during both periods, rising in the quarter to 37.4% from a year-ago 36.9%. For the nine-month period, gross margin increased to 38.5% from the year ago 37%. Operating expenses for the three months fell to $4.1 million from a year-ago $4.5 million but were up for the nine-month period to $14.1 million from a year-ago $13.1 million. The increase in operating expenses for the nine-month period was due primarily to higher variable expenses, such as outbound freight and commissions, resulting from higher sales and increased sales and promotional expenditures. OEM revenues were down for the quarter as well as for the nine-month period, with nine-month OEM revenues falling to $2 million compared with a year-ago $2.2 million, because of interrupted production by Japanese automaker customers. Nonetheless the company s OEM business remains stable, and their Japanese-based partners have returned to normal production after the earthquake and tsu- nami that reduced their operations in the second quarter. Audiovox Experiences Growth Audiovox reported higher net sales and net income for its fiscal second quarter, ended August 31. Net income for the quarter was $3.4 million, compared with net income of $600,000 in the prior year s second quarter. Net sales for the second quarter were $158.3 million, an increase of 22.5%, compared with net sales of $129.3 million reported in the comparable year-ago period. For the fiscal first half net sales were $323.7 million, an increase of 24.7% as compared with net sales of $259.6 million for the prior year s first half. First-half net income was $5.9 million, compared with a net income of $1.8 million last year. For the three- and six-month periods, ended August 31, electronics sales were $126.7 million and $259.0 million, an increase of 33.1% and 36.5%, respectively, over the comparable prior-year periods. Accessories sales were $31.6 million and $64.7 million, a decrease of 7.2% and 7.5%, respectively. For both periods, the electronics group was favorably impacted by the addition of Klipsch, improvements in the automotive OEM channel, both domestically and abroad, and increases in international operations of Audiovox. Offsetting these increases were lower sales of consumer electronics products and select groups in the audio category, as well as lower sales of accessory products attached to TV sales in the United States. As a percentage of net sales, electronics represented 80% of the net sales for the three and six months, ended August 31, and accessories represented the remaining 20% for these periods. 44 VOICE COIL

45 Operating income was $7.7 million, compared with operating income of $2 million in the comparable year-ago period. For the fiscal first half, operating income was $11.6 million, compared with an operating loss of $1.3 million in the prior year. Consumer Confidence Hits New Low Consumer sentiment in the overall economy is at its lowest point in the history of the CEA Indexes, the Consumer Electronics Association (CEA) announced. Consumer confidence in technology spending also fell in September. For the fifth consecutive month, consumer confidence in the overall economy has dropped, now to its lowest level in the history of the CEA Indexes, which began tracking in January In September, the CEA Index of Consumer Expectations (ICE) fell to 156.8, down two points from last month and six-and-a-half points lower than this time last year. Consumer confidence in technology also fell in September. After strong gains, the CEA Index of Consumer Technology Expectations (ICTE), which measures consumer expectations about technology spending, dropped two-and-a-half points to The ICTE is at its lowest level since May 2011, but remains up a point from this time last year. The CEA Indexes comprise the ICE and ICTE, which are updated on a monthly basis through consumer surveys. New data is released on the fourth Tuesday of each month. CEA has been tracking index data since January For more information, log on to CEAindexes.org. VC + R & D Measurement system Features: Multiple displays of min. 16 responses Waterfall Decay with Time curtain THD + 2 9th harmonics distortion 1/12-1/6-1/3 1/2 1/1 octave Anechoic FFT - Acoustic auto-delay 50 curves/responses/ts parameters SPL/Frequency, Imp., phase, export Soundcards: PCI/USB/Firewire/ASIO Headsets, USB/Bluetooth 19 hardware USB+25W Amp/48V Perfect replacement for MLSSA and LMS DECEMBER

46 Products & Services Index Advertiser Categories Page AAC Applications Acoustiques de Composites. D,L...15, 43 ACO Pacific, Inc.... K,N Acoustics First Corporation.... R ALMA International.... T... 9 Audience... B,C,H Audiostar Electronics Co., Ltd.... O audioxpress Beston Technology Corporation... D BMS Speakers GmbH... D Celestion Int'l.... D Creative Sound Solutions... D Dyne Analytics... N Eckel Industries.... N Etani Electronics Co., Ltd.... B,G,L,N EzPCB... C,N,O Faital USA... D Ferrotec Corporation... L Fluid Metering, Inc... J G.R.A.S Sound & Vibration.... K... 6 HiVi, Inc... D Jantzen Audio Denmark... L,O... 7 K & K Development.... N Klippel GmbH.... G,N Listen, Inc.... C,G,N... 2 LOUDsoft... G Materion Electrofusion.... B,L,O... 3 Menlo Scientific, Ltd.... B Monster Cable.... E Morel.... D Ningbo Yinzhou Huada Sound... F,L NTI-Americas... B,G,J,N One Magnet Electronic Co., Ltd.... I Pacific Audio Consulting... B Parts Express... L Precision Econowind, Inc..... O... 8 Prism Media Products... G Pulsus Technologies..... G... 5 Rotel Electronics... B Saati Tech... Q... 9 Solen Electronique, Inc.... C,D Suzuki Kanshi (Thailand) Co.,Ltd.... L Tang Band Industries Co.... D...39,41 Vance Dickason... B Wavecor Ltd.... F,H CATEGORY KEY A = ADHESIVES B = CONSULTANTS & ENGINEERS C = CROSSOVERS & PASSIVE COMPONENTS D = DRIVERS E = EMPLOYMENT OPPORTUNITIES F = ENCLOSURES & ENCLOSURE PARTS G = ENGINEERING/DESIGN SOFTWARE H = FINISHED SYSTEMS I = MAGNETS & EQUIPMENT J = MANUFACTURING EQUIPMENT K = MICROPHONES L = PARTS M = RECONING N = TEST EQUIPMENT O = VOICE COILS COMPONENTS & MATERIALS P = TRANSDUCERS Q = ACOUSTIC MESH R = ACOUSTICAL & SOUNDPROOFING MATERIALS S = AMPLIFICATION T = TRADE SHOW This product/services index is provided as a value-added service to our readers and advertisers. The publisher will not be held liable for any errors or deletions contained herein. Dayton Audio s OmniMic is a must-have for system integrators, acoustic engineers, and A/V installers. It was developed in collaboration with Liberty Audio, inventors of the Praxis analysis tool. The OmniMic provides quick and accurate measurements that will reduce installation time, saving you both labor and money. Just open the box and start testing in minutes! Dayton Audio s WT3 just got better the same great features as before, but now perfect for incoming or end-of-line QC inspections! DIY speaker builders will also fi nd the new capabilities useful when comparing multiple drivers for line array type systems. The WT3 is manufactured on state-of-theart equipment and uses precision surface-mount components. Try a WT3 and build better speaker systems! Distributed By: Tel: Pleasant Valley Dr. Springboro, OH In Asia: In Europe: In Canada: parts-express.com/vcm baysidenet.jp intertechnik.de solen.ca 46 VOICE COIL

47 Driving your loudspeaker to a higher end. Extensive R&D was devoted into our wide range of high-performance drive units, offering innovative technology, hand-made craftsmanship and outstanding acoustic performance. Made in Israel, all of our products are manufactured in the most stringent conditions to ensure consistency and high product quality. We understand the importance of having a stable supply of high quality drive units, R&D support, affordable prices and superb customer service. We invite you to discover morel s extensive line of raw drivers. Come visit us at 2012 International CES, January 10-13, Mobile audio: Venetian Suite Home audio: Venetian Suite Hamazmera St. Ness Ziona 70400, Israel, Tel.: info@morel.co.il

48 Prism Sound is now a global sales & support agent for: Loudspeaker design and analysis solutions electronic test, acoustic test......integrated dscope Series III analog and digital audio analyzers

20 VOICE COIL. Figure 7: BlieSMA T34A-4 SoundCheck CSD waterfall plot

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